A066553 Let N = 1357911131517192123252729313335373941434547495153555759616365676971..., the concatenation of the odd numbers. a(n) is the n-digit number formed from the digits of N starting from the {n(n-1)/2 +1}th digit. Omit any leading zeros.

1, 35, 791, 1131, 51719, 212325, 2729313, 33537394, 143454749, 5153555759, 61636567697, 173757779818, 3858789919395, 97991011031051, 71091111131151, 1711912112312512, 71291311331351371, 391411431451471491

Offset

1,2

Links

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Mathematica

With[{nn=20}, FromDigits/@TakeList[Flatten[IntegerDigits/@Range[1, (nn (nn+1)), 2]], Range[nn]]] (* Requires Mathematica version 11 or later *) (* Harvey P. Dale, Sep 23 2019 *)

Crossrefs

Sequence in context: A028162 A028160 A028107 * A137309 A028024 A226941

Adjacent sequences: A066550 A066551 A066552 * A066554 A066555 A066556

Keyword

nonn,base

Author

Amarnath Murthy, Dec 17 2001

Extensions

More terms from Hans Havermann, Sep 23 2002

Status

approved